Ratchet wrench

Abstract

A ratchet wrench includes a body which has a through hole, a first recess, a second recess, a top recessed area and a bottom recessed area to accommodate the ratchet wheel, the pawl, the switch unit, the top ring, the bottom ring, the top clip and the bottom clip. The ratchet wheel has a first pivotal portion, a top groove, a second pivotal portion and a bottom groove. The pawl has a notch. The switch unit is pivoted to control the movement of the pawl in the first recess. The top ring is located in the top recessed area and the bottom ring is located in the bottom recessed area. The top clip and the bottom clip respectively position the ratchet wheel, and restrict the top ring and the bottom ring from dropping from the body.

What is claimed is: 
     
         1 . A ratchet wrench comprising:
 a body having a through hole defined through a top and a bottom thereof, the through hole having a first recess defined in an inner periphery thereof, a center of the first recess located in the through hole, a diameter of the first recess being smaller than a diameter of the through hole, a second recess defined in an inner periphery of the first recess, a diameter of the second recess being smaller than the diameter of the first recess, the first recess being opened to the top and the bottom of the body, the second recess being opened to the top of the body and having a closed portion formed on the bottom of the body, an opening communicating with a lower end of the second recess, a first contact face and a second contact face defined in two sides of the opening, each of the first and second contact faces being a recessed and curved face, a top recessed area defined in the top of the body and sharing a common axis with the through hole, the top recessed area communicating with the first recess, a bottom recessed area defined in the bottom of the body and sharing the common axis with the through hole;   a ratchet wheel rotatably received in the through hole and having a ratchet portion defined in an outer periphery thereof, a connection portion defined through the ratchet wheel, a first pivotal portion and a second pivotal portion respectively formed on two ends of the ratchet wheel, the first pivotal portion having a top groove, the second pivotal portion having a bottom groove, the first pivotal portion pivotably engaged with the top recessed area, the second pivotal portion pivotably engaged with the bottom recessed area;   a pawl movably received in the first recess and having a toothed face defined in a front side thereof, the toothed face engaged with the ratchet portion of the ratchet wheel;   a switch unit rotatably connected to the second recess to control movement of the pawl in the first recess, a third pivotal portion formed on an end of the switch unit and having the same diameter as the switch unit cylindrical member;   a top ring received in the top recessed area and contacting a first shoulder formed between the top recessed area and the through hole, the top ring having a fourth pivotal portion defined in an inner periphery thereof, the fourth pivotal portion being pivotably engaged with the first pivotal portion, the top ring having a recessed portion which is defined in an outer periphery of the top ring, the recessed portion located between two first protrusions, the recessed portion being pivotably connected to the third pivotal portion, the recessed portion and the second recess co-axially mounted to the third pivotal portion of the switch unit, the two first protrusions closing the first recess in the top of the body;   a top clip engaged with the top recessed area and the top groove and contacting the top ring to restrict the top ring from separating from the ratchet wheel;   a bottom ring engaged with the bottom recessed area and contacting a second shoulder formed between the second recessed area and the through hole, an inner periphery of the bottom ring pivotably mounted to the second pivotal portion, the bottom ring having a second protrusion extending radially from an outer periphery thereof, the second protrusion closing the recess in the bottom of the body, and   a bottom clip engaged with the bottom recessed area and the bottom groove so as to contact the bottom ring, the ratchet wheel being restricted within the through hole by the top ring, the top clip, the bottom ring and the bottom clip.   
     
     
         2 . The ratchet wrench as claimed in  claim 1 , wherein an angle is defined between the inner end of the first recess and the inner periphery of the first recess, the angle is between 90 to 120 degrees. 
     
     
         3 . The ratchet wrench as claimed in  claim 2 , wherein the angle is between 90 to 100 degrees. 
     
     
         4 . The ratchet wrench as claimed in  claim 1 , wherein the top recessed area and the bottom recessed area are symmetrically located relative to the first hole. 
     
     
         5 . The ratchet wrench as claimed in  claim 1 , wherein the connection portion is a polygonal hole or a rectangular protrusion. 
     
     
         6 . The ratchet wrench as claimed in  claim 1 , wherein an outer diameter of the first pivotal portion is smaller than an outer diameter of the ratchet wheel. 
     
     
         7 . The ratchet wrench as claimed in  claim 1 , wherein an outer diameter of the second pivotal portion is smaller than an outer diameter of the ratchet wheel. 
     
     
         8 . The ratchet wrench as claimed in  claim 1 , wherein an outer diameter of the first pivotal portion is the same as an outer diameter of the second pivotal portion, the first and second pivotal portions are symmetrically located relative to the ratchet wheel. 
     
     
         9 . The ratchet wrench as claimed in  claim 1 , wherein the pawl has a notch defined in a middle portion of a rear side thereof, the pawl has a contact end defined each of two ends thereof, either one of the two contact ends selectively contacts the inner periphery of the first recess, the switch unit includes a switch member, a cap and a resilient member, the switch member has a cylindrical member which is pivotably located in the second recess, the cylindrical member has a reception hole which faces the notch, a lever extends radially from the cylindrical member which is pivotably located in the opening, two sides of the lever are shaped to be matched with the first contact face and the second contact face, the third pivotal portion is formed on one end of the cylindrical member, the resilient member and the cap are received in the reception hole, the resilient member is biased between an inner end of the reception hole and the cap which is engaged with the notch of the pawl. 
     
     
         10 . The ratchet wrench as claimed in  claim 1 , wherein the top clip and the bottom clip each are a resilient clip. 
     
     
         11 . The ratchet wrench as claimed in  claim 9 , wherein the top ring contacts the cap to locate the switch unit in the second recess. 
     
     
         12 . The ratchet wrench as claimed in  claim 1 , wherein an outer diameter of the first pivotal portion is the same as an outer diameter of the second pivotal portion, the two respective diameters of the first pivotal portion and the second pivotal portion are larger than a diameter of the ratchet portion. 
     
     
         13 . The ratchet wrench as claimed in  claim 1 , wherein an inner diameter of the top recessed area is the same as an inner diameter of the bottom recessed area. 
     
     
         14 . The ratchet wrench as claimed in  claim 1 , wherein the first recess in the top of the body includes two first extended recesses which communicate with the opening, the first recess in the bottom of the body includes two second extended recesses which communicates with the opening, the first protrusions of the top ring match the two first extended recesses. 
     
     
         15 . The ratchet wrench as claimed in  claim 14 , wherein the bottom clip includes a third protrusion extending radially from an outer periphery thereof, the third protrusion is overlapped onto the second protrusion, an outside of the second protrusion and an outside of the third protrusion contact the second extended recesses.